Protein Expression Services

GenWay provides customized solutions to each protein expression project. Our expert scientific staff has experience with difficult proteins and have produced more than 2,500 recombinant proteins. Whether your needs are small scale research or large scale cGMP, we can apply our experience to meet your needs. Services include E. coli expression, Mammalian expression, Yeast expression, and Antigen Preparation. Please use our convenient online Protein Expression Quote Form if you would get a quote or schedule a call to discuss your needs.

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  • Phone: 858.458.0866
  • Q: What Quality Control Should I Ask For?

    A: A standard QC procedure for a protein should at the very least contain a purity control (via SDS PAGE) and protein concentration (as determined by UV280 absorbance, colorimetric assays, or means specific to the target. Ultimately, the final specifications as defined by the customer will determine the final QC tests. Clearly defining a set of specifications and tolerances is critical to maintain customer and manufacturer on the same page.

    Q: What specifications should I think about when talking to the CRO

    Table 1 shows a general list of items to be taken into consideration, ultimately dependent on the downstream use of the material

    Specification Considerations
    Construct What does the final protein need to look like. Fusions, tags, full length or fragments
    Activity Active or inactive protein
    Endotoxin What are the endotoxin requirements
    Lot size What is the minimum volume of material required per lot
    Lots per year How many lots of material does the customer require every year
    Final buffer Including final buffer preparation, ionic strength, pH
    Protein Quality Protein concentration, purity


    Q: What is the best purification strategy for manufacturing large scale protein production?

    A: The best purification strategy for manufacturing is the most efficient cost and labor wise can give lot-to-lot reproducible results. You should look for a scalable and reproducible protocol, with as few steps as possible to achieve the goal, to reduce variables and points of failure.

    Q: How do I select the right expression system?

    A: Selecting the right expression host, both for the required specifications and scale is essential. For example while expression in prokaryotic systems is usually the most economical for scaling, if the final product requires very low endotoxin, or post-translational modifications are critical to the downstream application, eukaryotic systems (mammalian or insect cells), should be selected. Likewise, if endotoxin, or PTMs are not important downstream.

    Q: I have a protein that I can produce on a small scale. How do I transfer the small scale to large scale manufacturing?

    A: We phase the process into 3 stages:

    Phase1: An "R&D stage", which usually takes the longest, where we either do a technology transfer if you already have the technology (expression vector, expression host, small scale protocol) or the historical knowledge of the project, or we develop the expression construct, and optimize expression and purification methods based on your specifications. The cost of this process will depend on the difficulty of the target. but usually between $6,000 - $12,000 USD. We do have customers that, because of the challenge of the protein, decide to go to an hourly rate. The cost ends up being about the same, but it allows more flexibility on either end to change or add experiments as need be. With either option we set up weekly or biweekly meetings to discuss the progress so that we're all on the same page. This stage may take 6 - 8 weeks, again depending on the target.

    Phase 2: After the initial R&D stage, we move on to a scale-up or "Engineering" stage, where we adapt the process to large scale, and begin the process of moving the procedure into our quality system, generate all of the documentation, generate a manufacturing-quality master cell bank, and ultimately establish both, the scalable expression and purification protocols as well as the exit QC that ensures that the we meet your specifications AND that the product behaves consistently in you hands. This process takes again, about 6 weeks, and price will be very much dependent on scale ( usually about $20,000 USD).

    Phase 3: In the final "Validation" stage, we produce 3 lots to assure reproducibility, already within our quality system, to-scale, and only modifying protocols slightly, if required. Because that material is already in the quality system, you can use them in your manufacturing process or procedure. At this stage we usually quote per-milligram or per-gram price, which will be dependent on the cost of the materials and the effort.

    Q: How do you ship your material?

    A: We ship most proteins overnight, frozen in dry ice.

    Q: Do you do yeast expression?

    A: Yes. With yeast we recommend testing 2 sets of constructs (full length and truncation) in S. cerevisiae (for intracellular expression) and P. pastoris (secreted expression). If secreted expression in P. pastoris works, your yields will be higher and easier to reach.

    We also recommend testing flask expression (limit 12L) and fermentor vessel expression (20L lots) in parallel. to determine which one can ultimately produce your specified yield the fastest, as well as a small-scale purification test, to determine optimum conditions